If you refer to an Standard then you must pass the test defined in this Standad in an certified test laboratory.
The enclousure is very inportant in some aspects like EMC an others.
Depending of your country laws you must coumplish some standards and tests.
There are a lot of standars in vibration, humidity, heat.. EN, ISO, DIN, BS, UNE....
I dont know what are aplicable in your country.

Regards.